scholarly journals Role of Interactions in the Energy of the Spin Resonance Peak in Fe-Based Superconductors

2019 ◽  
Vol 289 ◽  
pp. 212-217 ◽  
Author(s):  
Yuliya N. Togushova ◽  
Maxim Korshunov
Keyword(s):  
Resonance Energy ◽  
Energy Scale ◽  
Resonance Peak ◽  
Characteristic Energy ◽  
Iron Based Superconductors ◽  
Hubbard Interaction ◽  
First Case ◽  
Spin Resonance ◽  
Spin Response

We consider the spin response within the five-orbital model for iron-based superconductors and study two cases: equal and unequal gaps in different bands. In the first case, the spin resonance peak in the superconducting state appears below the characteristic energy scale determined by the gap magnitude, 2ΔL. In the second case, the energy scale corresponds to the sum of smaller and larger gap magnitudes, ΔL+ΔS. Increasing the values of the Hubbard interaction and the Hund's exchange, we observe a shift of the spin resonance energy to lower frequencies.

scholarly journals Depression among health care students in the time of COVID-19: the mediating role of resilience in the hopelessness–depression relationship

2021 ◽  
pp. 008124632199445
Author(s):  
Tammy-lee Pretorius
Keyword(s):  
Health Care ◽  
Traumatic Event ◽  
National Level ◽  
Depression Scale ◽  
Health Care Students ◽  
Mediating Role ◽  
First Case ◽  
Hopelessness Depression ◽  
The World

COVID-19 spread rapidly across the world, and by March 2020, the first case of COVID-19 was identified in South Africa. Lockdown-related measures such as restricted movement and isolation were implemented to contain the virus. Combined with these measures, factors such as economic decline, job losses, and food shortages can cause numerous mental health sequelae such as depression. Feelings of hopelessness and helplessness as well as cases of suicide have been reported around the world due to the pandemic and the associated feelings of anxiety and depression. The aims of this study were to investigate levels of hopelessness and depression in a sample of health care students. A random sample of students ( N = 174) enrolled in a health sciences programme at the University of the Western Cape completed the Beck Hopelessness Scale, the Center for Epidemiological Studies Depression Scale, and a three-item Resilience Scale. The results revealed high levels of hopelessness and depression compared to previously reported normative data for these scales. In addition, the indirect effects of hopelessness on depression were significant, demonstrating the mediating role of resilience in the hopelessness–depression relationship. These results highlight a call for universities to take proactive measures in providing students with free and easily accessible resources to help them cope and manage stress during a traumatic event. More importantly, at a national level, preventive measures should be implemented to strengthen resilience in young adults.

scholarly journals Environmentally persistent free radicals are ubiquitous in wildfire charcoals and remain stable for years

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Gabriel Sigmund ◽  
Cristina Santín ◽  
Marc Pignitter ◽  
Nathalie Tepe ◽  
Stefan H. Doerr ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Free Radicals ◽  
Reactive Oxygen ◽  
Resonance Spectroscopy ◽  
Oxygen Species ◽  
Pyrogenic Carbon ◽  
Spin Resonance ◽  
Long Time ◽  
High Concentrations

AbstractGlobally landscape fires produce about 256 Tg of pyrogenic carbon or charcoal each year. The role of charcoal as a source of environmentally persistent free radicals, which are precursors of potentially harmful reactive oxygen species, is poorly constrained. Here, we analyse 60 charcoal samples collected from 10 wildfires, that include crown as well as surface fires in forest, shrubland and grassland spanning different boreal, temperate, subtropical and tropical climate. Using electron spin resonance spectroscopy, we measure high concentrations of environmentally persistent free radicals in charcoal samples, much higher than those found in soils. Concentrations increased with degree of carbonization and woody fuels favoured higher concentrations. Moreover, environmentally persistent free radicals remained stable for an unexpectedly long time of at least 5 years. We suggest that wildfire charcoal is an important global source of environmentally persistent free radicals, and therefore potentially of harmful reactive oxygen species.

Was tut ein Geschichtsschreiber?

Philologus ◽  
2020 ◽  
Vol 164 (2) ◽  
pp. 250-2689
Author(s):  
Thomas Kuhn-Treichel
Keyword(s):  
First Case ◽  
Value Judgements ◽  
Modern Era

AbstractLucian’s work De historia conscribenda not only presents reflections on how one should or should not write history, but also illustrates possible ways to represent the authorial activity of a historian (i. e. how one writes ‘metahistory’). In this, two basic forms can be distinguished, both of which can be understood from a narratological perspective as metalepses. In the first case, the historian is represented as the direct originator of the action; in the second he acts as a mere observer, but one who moves spatially in and with his action. Both forms of statement stand within traditions of motifs that can be traced from antiquity through to the modern era; yet Lucian nonetheless makes an innovative contribution by inscribing value judgements into the motifs. The result is the suggestion that the historian fulfils the role of observer, while the role of originator turns out to be more apt for the poet than for the historian. This permits far-reaching conclusions to be drawn about the conception of poetry and historiography as a whole.

Properties of Catalytic-Cvd Amorphous Silicon-Germanium (a-SiGe:H)

1990 ◽  
Vol 192 ◽  
Author(s):  
Hideki Matsumura ◽  
Masaaki Yamaguchi ◽  
Kazuo Morigaki
Keyword(s):  
Amorphous Silicon ◽  
Silicon Germanium ◽  
Hydrogenated Amorphous Silicon ◽  
Chemical Vapor ◽  
Characteristic Energy ◽  
Optical Band Gaps ◽  
Spin Resonance ◽  
Amorphous Silicon Germanium ◽  
Conductive Properties ◽  
Hydrogenated Amorphous

ABSTRACTHydrogenated amorphous silicon-germanium (a-SiGe:H) films are prepared by the catalytic chemical vapor deposition (Cat-CVD) method using a SiH4, GeH4 and H4 gas mixture. Properties of the films are investigated by the photo-thermal deflection spectroscopy (PDS) and electron spin resonance (ESR) measurements, in addition to the photo-conductive and structural studies. It is found that the characteristic energy of Urbach tail, ESR spin density and other photo-conductive properties of Cat-CVD a-SiGe:H films with optical band gaps around 1.45 eV are almost equivalent to those of the device quality glow discharge hydrogenated amorphous silicon (a-Si:H).

FIRST CASE SERIES OF VENOUS SINUS STENTING IN IIH PATIENTS IN WALES

2015 ◽  
Vol 86 (11) ◽  
pp. e4.113-e4
Author(s):  
Gauhar Abbas Malik ◽  
Yogish Joshi
Keyword(s):  
Intracranial Hypertension ◽  
Case Series ◽  
Headache Disorder ◽  
Venous Sinus ◽  
First Line ◽  
Venous Stenting ◽  
First Case ◽  
Sinus Stenosis

BackgroundIdiopathic Intracranial Hypertension (IIH), is defined by increased cerebral spinal fluid (CSF) pressure in the absence of other causes of intracranial hypertension. There has been recent interest in the role of intracranial venous sinus stenosis in IIH. The raised pressures in IIH are argued to worsen by the secondary appearance of the venous sinus stenosis.Objective5 patients have undergone endovascular pressure measurement in Wales and their clinical details including history, examination, initial management, neuroimaging pre- and post venous stenting, and follow-up (6–24 months) to provide the first case study of patients undergoing Venous sinus stenting in Wales.Methods5 patients with IIH refractory to first line treatments underwent venography and manometry and 4 patients underwent stenting of the venous sinuses after this procedure had shown a pressure gradient proximal to stenosis in the lateral sinuses.ResultsThree patients were rendered asymptomatic, two were improved including one patient unmasking a different headache disorder following treatment.ConclusionsStenting in venous stenosis provides a further treatment option to patients refractory to first line treatments with IIH. This case series highlights in selected cases treatment is promising with good outcomes.

scholarly journals Microstructure and Electromagnetic Properties of Ni-Zn-Co Ferrite up to 20 GHz

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Charalampos Stergiou
Keyword(s):  
Wall Motion ◽  
Wave Attenuation ◽  
Domain Wall Motion ◽  
Electromagnetic Properties ◽  
Complex Permeability ◽  
Microwave Dielectric ◽  
Zn Ferrite ◽  
Spin Resonance ◽  
Production Stages

The present paper examines the relation between different developed microstructures and the microwave electromagnetic properties in Ni-Zn-Co ferrite. To this end, the Ni0.25Zn0.25Co0.5Fe2O4composition has been prepared with the conventional ceramic process with varied prefiringTP(750°C, 1000°C) and sinteringTStop temperatures (1200°C, 1250°C). When lower temperatures are applied in these production stages, incomplete microstructures with low density, higher porosity, or finer grains are achieved. On account of these features, the contributions of domain wall motion and spin rotation to the complex permeabilityμ⁎(f)move to higher frequencies, whereas microwave dielectric permittivityε⁎(f)is decreased. In particular in conjunction with the high Co content, the wall relaxation and spin resonance are interestingly forced to occur at 850 MHz and 8.05 GHz, respectively. Regarding the electromagnetic wave attenuation, the ferrite annealed at lower temperatures exhibits strong return loss peaks at higher frequencies, but without other performance improvement. We should notice that the variations in sintering temperatureTSyield the maximum changes in the recorded parameters, including the coercive field,μ⁎(f),andε⁎(f), indicating the inferior role of prefiringTPin Ni-Zn ferrite.

scholarly journals Role of Immunotherapy in Pulmonary Angiosarcoma: A Case Report

2021 ◽  
pp. 797-801
Author(s):  
Quang Tien Nguyen ◽  
Anh Tuan Pham ◽  
Thuy Thi Nguyen ◽  
Tam Thi Thanh Nguyen ◽  
Ky Van Le
Keyword(s):  
Case Report ◽  
Poor Prognosis ◽  
Checkpoint Inhibitor ◽  
Therapeutic Strategies ◽  
Clinical Entity ◽  
Rare Clinical Entity ◽  
Excellent Response ◽  
First Case

Pulmonary angiosarcoma is a rare clinical entity with a poor prognosis and no established therapeutic strategies. We present the first case to our knowledge of metastatic pulmonary angiosarcoma, treated with checkpoint inhibitor immunotherapy, and have an excellent response. Until now, patient has been treated with immunotherapy for 1 year, and his disease is stable and well-tolerated.

The role of chemical composition in the synthesis of Ca/K-1144 iron based superconductors

2021 ◽  
pp. 159202
Author(s):  
Andrea Masi ◽  
Achille Angrisani Armenio ◽  
Giuseppe Celentano ◽  
Aurelio La Barbera ◽  
Alessandro Rufoloni ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Iron Based Superconductors ◽  
Iron Based

scholarly journals Pneumocystis Melanins Confer Enhanced Organism Viability

2006 ◽  
Vol 5 (6) ◽  
pp. 916-923 ◽  
Author(s):  
Crystal R. Icenhour ◽  
Theodore J. Kottom ◽  
Andrew H. Limper
Keyword(s):  
Fungal Pathogen ◽  
Pneumocystis Carinii ◽  
Environmental Stressors ◽  
Resonance Spectroscopy ◽  
Reverse Transcription Pcr ◽  
Spin Resonance ◽  
Opportunistic Fungal Pathogen ◽  
Adverse Environmental Conditions ◽  
Previous Identification

ABSTRACT Pneumocystis continues to represent an important opportunistic fungal pathogen of those with compromised immunity. Thus, it is crucial to identify factors that affect its viability and pathogenicity. We previously reported the first identification of melanins in Pneumocystis. In the present study, we sought to further characterize these components and define the function for these melanins. Melanins extracted from Pneumocystis and melanized Pneumocystis cells were analyzed by electron spin resonance spectroscopy, revealing spectra consistent with melanins from other fungi. Immunofluorescence assays using anti-melanin monoclonal antibodies showed that melanins are widely present across Pneumocystis host species, including mouse-, ferret-, and human-derived Pneumocystis organisms, as well as Pneumocystis carinii derived from rat. Using immunoelectron microscopy, melanins were found to localize to the cell wall and cytoplasm of P. carinii cysts, as well as to intracystic bodies within mature cysts. Next, the role of melanins on the maintenance of Pneumocystis viability was determined by using quantitative reverse transcription-PCR measurement of the heat shock protein mRNA under adverse environmental conditions. Using a new method to promote the melanization of Pneumocystis, we observed that strongly melanized Pneumocystis retained viability to a greater degree when exposed to UV irradiation or desiccation compared to less-pigmented organisms. These studies support our previous identification of Pneumocystis melanins across the genus, further characterize these Pneumocystis components, and demonstrate that melanins protect Pneumocystis from environmental stressors.

scholarly journals The Regulator of Nitrate Assimilation in Ascomycetes Is a Dimer Which Binds a Nonrepeated, Asymmetrical Sequence

1998 ◽  
Vol 18 (3) ◽  
pp. 1339-1348 ◽  
Author(s):  
Joseph Strauss ◽  
M. Isabel Muro-Pastor ◽  
Claudio Scazzocchio
Keyword(s):  
Nitrate Assimilation ◽  
Binding Studies ◽  
Binding Ability ◽  
Zinc Cluster ◽  
First Case ◽  
Vitro Binding ◽  
Nitrate Induction ◽  
Dna Complex

ABSTRACT The regulation of nitrate assimilation seems to follow the same pattern in all ascomycetes where this process has been studied. We show here by in vitro binding studies and a number of protection and interference techniques that the transcription factor mediating nitrate induction in Aspergillus nidulans, a protein containing a binuclear zinc cluster DNA binding domain, recognizes an asymmetrical sequence of the form CTCCGHGG. We further show that the protein binds to its consensus site as a dimer. We establish the role of the putative dimerization element by its ability to replace the analogous element of the cI protein of phage λ. Mutagenesis of crucial leucines of the dimerization element affect both the binding ability of the dimer and the conformation of the resulting protein-DNA complex. This is the first case to be described where a dimer recognizes such an asymmetrical nonrepeated sequence, presumably by each monomeric subunit making different contacts with different DNA half-sites.

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